Question

我正在构建一个Angular / Javascript / Ionic / Cordova应用程序。

我有一个函数，我调用下面的数组，它存储为变量（existingEntries）

categories: Array [276]
 [0...99]
   0: Object
     id: 288
     exclude: false   
   1: Object
     id: 320
     exclude: true

此函数会抓取该数组中的所有元素，以查看值exclude是否设置为true或false

    var existingEntries = $scope.categoryList;
    if(existingEntries == null) existingEntries = [];
        for (var i = 0; i < existingEntries.length; i++) {
            if (existingEntries[i]['exclude'] == true) {
                $scope.addLocalExcludedCategories(i);
            } else if (existingEntries[i]['exclude'] == false) {
                $scope.removeLocalExcludedCategories(i);
            }                       
    }

完成此操作后，将调用其他相关函数（addLocal ..并删除Local ...）来存储id。下面是addLocal ..函数，这可以工作，但是当我反复运行这些代码时，我得到了重复，我相信它可以更好地编码。我正在使用localstorage，因为我需要在本地保存数组，但如果你有其他解决方案会很棒。

    $scope.addLocalExcludedCategories = function(catID) {
    console.log("addLocalExcludedCategories Called")
    //Add Item to Excluded Categories Variable
    var existingEntries = JSON.parse(window.localStorage.getItem("ExcludedCategories"));                            
    if(existingEntries == null) existingEntries = [];

    var entryId = catID;
    var entry = {
        'id': entryId,
    };
    existingEntries.push(entry);        

    window.localStorage.setItem("ExcludedCategories", JSON.stringify(existingEntries));
    $scope.ExcludedCategories = window.localStorage.getItem("ExcludedCategories");      
}

此处还有删除功能，因为我找到了将排除值设置为true而不是false的id，因此无法正常工作。

$scope.removeLocalExcludedCategories = function(catID) {    
console.log("removeLocalExcludedCategories Called")
    //Remove Item to Excluded Categories Variable
    var existingEntries = JSON.parse(window.localStorage.getItem("ExcludedCategories"));
    if(existingEntries == null) existingEntries = [];

    for (var i = 0; i < existingEntries.length; i++) {
        if (existingEntries[i]['id'] == catID) {
            console.log(i);
            existingEntries.splice(i, 1);
        }
    }
    //console.log("Remove Categories >>>");
    //console.log(existingEntries);
    window.localStorage.setItem("ExcludedCategories", JSON.stringify(existingEntries));
    $scope.ExcludedCategories = window.localStorage.getItem("ExcludedCategories");
    console.log($scope.ExcludedCategories);
}

希望这有意义，并提前感谢！

Answer 1

您没有检查 existingEntries 数组中是否已存在条目，这就是您获取欺骗的原因 试试此代码......

$scope.addLocalExcludedCategories = function(catID) {
    console.log("addLocalExcludedCategories Called")
    //Add Item to Excluded Categories Variable
    var existingEntries = JSON.parse(window.localStorage.getItem("ExcludedCategories")) || [];

    var entryId = catID;
    var entry = {
        'id': entryId,
    };
    if(existingEntries.length > 0){
    existingEntries.forEach(function(entry){
     if(entry.id !== entry.id){
      existingEntries.push(entry); 
    }
    });

Answer 2

使用ng-if语句计算出来，然后在本地存储数组，然后在调用时解析它。

$scope.ifCatExcludedTerms = function(sent_id){
    var doesNotExist = true;
    arraytosearch = JSON.parse(localStorage.getItem("categoryListMem"));
    //console.log (sent_id);
        for (var i = 0; i < arraytosearch.length; i++) {
            if (arraytosearch[i]['id'] == sent_id) {
                doesNotExist = false;
            }
        }
    return doesNotExist;
}

从数组中获取ID，存储它并在本地删除它

2 个答案: